<!DOCTYPE html>
<html lang="en">

<head>
    <meta charset="UTF-8">
    <meta name="viewport" content="width=device-width, initial-scale=1.0">
    <meta http-equiv="X-UA-Compatible" content="ie=edge">
    <title>Document</title>
    <style>
        /* input type="submit" 时给边框不会改变它的width.height*/
        * {
            margin: 0px;
            padding: 0px;
        }
        input{
            width: 100px;
            height: 30px;
            border: 1px solid #333;
            outline: none;
        }
        .btn{
            width: 102px;
            height: 32px;
        }
    </style>
</head>

<body>
    <div>
        <input type="text">
    </div>
    <div>
        <input type="submit" value="提交" class="btn">
    </div>
</body>

</html>